Hi missil3, I agree with sdebock. For the inflatable structure using uniform pressure methods using fluid inflators to model inflastion for CFD simulation would be a good idea than using implicit methods.
I agree with you Drej, by using pre-tension to belt with the force in static analysis we should use static analysis results to do a pre-stressed modal analysis for stiffened structure.
You can refer to 3.11. Prestressed Modal Analysis in...